a="  Ai Zi mai ti shi wo er  "
print(a.upper())
print(a.lower())
print(a.find("i"))
print(a.rfind("i"))
print(a.index("Zi"))
print(a.startswith("Ai"))
print(a.endswith("er"))
print(len(a))
print(len(a.lstrip()))
print(len(a.rstrip()))
print(len(a.strip()))
print(a)
print(a.lstrip())
print(a.rstrip())
print(a.strip())